Currently, in the diaplasis of fracture, e.g., zygomatic fracture, a single hook is generally used. However, it is sometimes difficult to obtain good diaplasis results just by depending on the single hook to retract the fractured bone segment, because human hands lack sufficient explosive force, or the force cannot be easily controlled once started. As a result, full traction reduction may not be achieved or the fractured ends may be over displaced under excessive force.